The acquisition of first language is one of the most interesting and also most mysterious phenomena studied by linguists. This phenomenon is considered unique, because it involves various factors and variables in its formation process. In relation to the problem of language acquisition, several theories have been presented from a variety of perspectives that range from naturalism to theories with an emphasis on social aspects of language development as well as theories that address human cognitive abilities. According to one view, young children have unique tacit characteristic which prepares them for acquisition of the first language. The amazing ability to understand the principles and rules of language and the knowledge of the hierarchical nature of syntax is one of the most important of these features. The acquisition of lexical meanings of a language also forms an integral part of the process of acquisition of the first language. Clark (2009) recorded the very first words produced by her own child. By recording the first fifty words produced by her child. She pointed out that these words refer to various categories such as man, food, body, clothing, animals, vehicles, toys, objects in the home, daily activities, and states. A review of these categories shows that at least the initial words produced by children are more semantically reflected from the environment around them. Acquisition of the meaning of words, on the other hand, requires the establishment of a kind of conceptual relationship among the acquired terms. In the sense that children must learn knowledge of lexical relations among acquired terms like synonymy and antonymy and so on. The semantic relation of antonymy is one of the most interesting of these relationships. Whether children attain the ability to understand and produce the relation of antonymy or how to apply it in the development of their linguistic abilities, has given rise to multiple questions, and different research programs. In linguistic and especially in the lexical semantic tradition, the study of the conceptual relationships between the vocabulary of each language and the way in which, those concepts are related to each other is called the semantic relations. The study of the semantic relations of antonymy in the process of acquisition of the first language can be considered in two general directions. First, studying the crucial role of this group of relationships in the formation of interlanguage meanings, and second, seeking to understand the role of this group of relationships in the process of developing the cognitive knowledge of the child from himself and his environment and its reflection in his language. On the other hand, due to the lack or even absence of a study in this language, the study is one of the first research activities which adds to the necessity of two more studies. The semantic relation of antonymy is one of the semantic relations which has been studied by many linguists. This group of linguists have mentioned various types of antonymy relations, such as gradable antonyms, complementary antonyms, and converse, directional and lexical antonyms. The order and process of acquiring antonym words in first language acquisition have been investigated in different fields of research during last decades and researchers have sought to explain this phenomenon using various techniques and methods. But the process of acquiring the antonym words in Persian language has not been given full consideration. The present research seeks to determine in what age and what order Persian speaking children produce different types of antonym words (graded, complementary, reciprocal and inverse), and whether the gender in learning such antonyms plays a meaningful role. Working towards this goal, in the present study which is a descriptive-analytical and cross-sectional type within the theoretical framework introduced by Murphy (2003) and her metalinguistic approach, 64 children and five pairs of antonym words for each four antonym types called complementary, reciprocal, gradable and reverses were selected. Children, both male and female in equal number, were between 5 to 8 years old and in four subgroups of ages, from 4.5 to 5.5, 5.5 to 6.5, 6.5 to 7.5, and 7.5 to 8.5. The participants of this study were selected from three kindergartens and one English language institute. After completing three homogenization tests from the International Test of Language Development (TOLD-3) in various phonological, syntactic and semantic fields, using the method of word game, the antonym pairs produced by children were extracted. Then, the data were analyzed by SPSS software. The findings indicated that, apart from gradable antonyms, the semantic growth of children in the production of antonym pairs would increase with increasing age. The results showed that the best use was made from gradable antonyms and the least use belonged to reciprocal antonyms.

Raghibdost, Sh & Qaleno, E. (2015) Application of spatial, syntactic and contextual features in the process of children conceptual development. Journal of Linguistics and Dialects of Khorasan. 10, 51-67 [In Persian].

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